Dynamic Semantics with Choice Functions

Abstract

Over the last two decades, semantic theory has been marked by a continuing shift from a static view of meaning to a dynamic one. The increasing interest in extending semantic analysis from isolated sentences to larger units of discourse has fostered the intensive study of anaphora and coreference, and this has engendered a shift from viewing meaning as truth conditions to viewing it as the potential to change the "informational context". One of the central problems of discourse analysis is the treatment of anaphoric expressions, of discourse pronouns and definite NPs. The traditional solution is to take pronouns as bound variables and to analyze definite NPs by means of the Russellian iota inversum operator; and this solution is usually taken over also by those semantic theories which take the dynamics of language at face value. However, as we try to show, theories falling in with this approach necessarily stop half way in the dynamic enterprise and, therefore, cannot achieve a satisfactory semantical analysis of anaphora. In the present paper we propose to apply the dynamic approach uniformly to all expressions. We give a dynamic treatment not only to meanings of sentences and supersentential units of discourse, but also to those of pronouns and NPs. This is possible by exploring the intuitive idea of salience and by its formalization by means of choice functions. A definite NP the P is taken to refer to the most salient P (to that entity which is yielded by the actual choice function for the set of all P’s); discourse pronouns are then considered as equivalent to certain definite NPs. Thus, the mechanism of choice manages to supplant both the apparatus of binding of variables (or discourse markers), on the one hand, and the Russellian analysis of definite NPs, on the other. This enables us to represent all anaphoric expressions uniformly. Salience, however is not a global and static property of a discourse, but rather a local and dynamic one an indefinite NP can change a given salience by raising a new entity to the most salient one.1 Therefore, a linguistic expression is semantically characterized neither by its truth conditions, nor by its potential to